About this product
Part Number: A-Z103BU
The NEW William Optics Zenithstar 103 APO features an air-spaced doublet lens with an Ohara FPL-53 ED glass element and fully multi-coated optics for high resolution, high contrast images virtually free of false-colour.
Despite it's large 103mm objective diameter it is surprisingly compact and very solid! Many airlines will accept it as carry-on luggage. An ideal size for serious observations of deep sky objects and planets.
Versatile f/6.9 native focal ratio or f/5.5 when used with matching 0.8x flattener / reducer.
Supplied with mounting rings, guiding rings and Vixen-style dovetail bar.
CNC machined aluminium for a superior fit and finish.
Heavy duty, dual speed 2.5" 1:10 R&P focuser. A popular choice for imaging.
Available in Blue, Red or Gold anodised.
Ohara FPL-53 vs FPL-51 ED Glass
The dispersion properties of ED and SD glass elements are important in determining the overall colour correction. The abbe index is used to quantify the 'partial dispersion' of a particular glass. Pure Fluorite offers the highest partial dispersion at around 94.99 V, Ohara FPL-53 glass is very close to Fluorite at 94.93 V and is often referred to as Synthetic Fluorite. FPL-53 is also noticeably better than Ohara's lower spec' FPL-51 glass which offers an abbe index of 81.54 V.
- 103mm f/6.9 Doublet air-spaced APO
- CNC machined ultra-high precision lens cell
- FPL-53 ED glass element for enhanced colour correction
- 2.5" Heavy Duty, dual-speed rack & pinion focuser
- 0.8x Reducer / Flattener available separately
- Innovative Bahtinov mask cover included!
- Supplied with mounting rings, guiding rings, CNC carry handle, Vixen-style dovetail bar and Bahtinov mask cover
Telescope Field of View Simulator
What's in the box
- Telescope OTA
- Mounting Rings
- Guidescope Rings
- Carry Handle
- Vixen-Style Dovetail
- Bahtinov Mask Cover
|Aperture ||103 mm |
|Focal Ratio ||F/6.9 |
|Focal Length ||710 mm |
|Objective Type ||ED Doublet, Air Spaced, |
Fully Multi-Coated, SMC coating.
|Lens Shade ||Retractable |
|Tube Weight ||9.6lbs. (4.36 kg) - Including dovetail & rings |
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